hey i got a muffler to put on my rocco, a dual tip 2.5 i think. my question is should i just put the muffler on with the stock piping. or should i replace it with some straight piping. i was under the impression that stock is 2.25 anyways (which is what i would replace it with, so whats the point). is it worth it to replace the piping? i have a 16v btw. thanks